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The liver regenerates by progenitor cells when it is damaged in chronic liver diseases and extensive damage. The progenitor cells, also termed "oval cells" according to their morphological traits, can differentiate into hepatocytes and bile duct cells in vivo. To better understand the transcriptional pattern that accompanies the hepatic differentiation of oval cells, we applied cDNA microarray to analyze the oval cell-derived liver epithelial progenitor cells (LEPCs) during in vitro induced differentiation. Upon exposure to sodium butyrate, a histone deacetylase inhibitor, cultured LEPCs differentiate and express functional hepatocyte markers albumin, tryptophan 2, 3-dioxygenase and alcohol dehydrogenase. For expression profiling, cells were harvested at 6 h, 12 h, 1 d, 3 d and 7 d after exposure to sodium butyrate. After analyzing the microarray data by SOM clustering, total of 796 differentially regulated genes were grouped into 48 clusters. Consistent with the phenotype change of LEPCs after sodium butyrate treatment, many hepatocyte functional genes are revealed by analyzing the clusters containing genes up-regulated through all the time points. The clusters, containing down-regulated genes immediately after the induction, are also analyzed. The microarray data was validated by analyzing the expression of selected genes by quantitative real-time PCR. A set of genes expressed synergistically in these clusters may play a central role during the process of differentiation. Sodium butyrate decreases cyclin B1 and Cdk4 expression, which would be associated with LEPCs growth arrest shortly after treatment. Bmi1, a polycomb group protein, is also down-regulated immediately after treatment and remains at a low level during the induction. These findings highlight the key molecular mechanisms by which sodium butyrate, mediates its effects on cell growth arrest and induction of differentiation. In conclusion, our data reflect a global view of gene expression during hepatic differentiation of LEPCs induced by sodium butyrate.

Background & Aim: Shortage of donor hepatocytes limits hepatocyte transplantation for clinical application. Induced hepatic stem cells (iHepSCs) have capacities of self‐renewal and bipotential differentiations. Here, we investigated whether iHepSCs could be extensively expanded, and whether they could differentiate into sufficient functional hepatocytes as donors for transplantation therapy after their extensive expansions. Methods: Murine extensively expanded iHepSCs (50‐55 passages) were induced to differentiate into iHepSC‐Heps under a chemically defined condition. iHepSC‐Heps were proved for carrying morphological hepatocyte characters and hepatocytic functions including low‐density lipoprotein uptake, glycogen storage, CLF secretion, ICG uptake and release, Alb secretion, urea synthesis and metabolism‐relative gene expressions respectively. Next, both iHepSCs and iHepSC‐Heps were transplanted into Fah‐/‐ mice respectively. Both liver repopulation and alleviation of liver function were compared between two transplantation groups. Results: Murine iHepSCs still maintained the capacities of self‐renewal and bipotential differentiations after extensive expansion. The efficiency for the functional hepatocyte differentiation from extensively expanded iHepSCs reached to 72.64%. Transplantations of both extensively expanded iHepSCs and iHepSC‐Heps resulted in liver engraftment in Fah‐/‐ mice. Survival rate of Fah‐/‐ mice recipients and level of liver repopulation were 50% and 20.32 ± 4.58% respectively in iHepSC‐Heps group, while 33% and 10.4 ± 4.3% in iHepSCs group. Conclusions: Extensively expanded iHepSCs can efficiently differentiate into hepatocytes in chemical defined medium. Transplantation of iHepSC‐Heps was more effective and more efficient than transplantation of iHepSCs in Fah‐/‐ mice. Our results suggested an innovative system to obtain sufficient hepatocytes through hepatic differentiation of iHepSCs generated by lineage reprogramming. [ABSTRACT FROM AUTHOR]

Examines the existence of hepatic stem cells (HSC) in the spleens of mice. Replacement demands of cellular losses; Role of HSC in hepatocarcinogenesis; Preparation of donor cells.

Peripheral nerve injury (PNI) is encountered relatively commonly in the clinic and often results in long-term functional deficits. Research to develop methods to improve regeneration following nerve injury is ongoing. Numerous studies have shown that adipose-derived stem cells (ADSCs) promote the regeneration of peripheral nerve injury; however, the mechanism is unclear. Autophagy, a highly conserved intracellular process responsible for maintaining cellular homeostasis, and Schwann cells (SCs), play important roles in regeneration after PNI. In the present study, we explored the effect and mechanism of exosomes produced by adipose-derived stem cells (ADSC-Exos) on autophagy of SCs in PNI, as well as their effect on the regeneration of the nerve myelin sheath. The levels of autophagy and the expression of karyopherin subunit alpha 2 (Kpna2) in SCs increased markedly after the sciatic nerve was injured in SCs (SNI-SCs). The enhanced autophagy and the upregulated Kpna2 in SNI-SCs were inhibited after treatment with ADSC-Exos in vivo and in vitro. The effect of ADSC-Exos on inhibiting SC autophagy was blocked by overexpression of Kpna2 in SNI-SCs. Using quantitative real-time reverse transcription PCR, ADSC-Exos were demonstrated to contain a large amount of miRNA-26b, which was predicted to regulate Kpna2 on the TargetScan website. The effect of ADSC-Exos on inhibiting SCs autophagy was blocked after the silencing of miRNA-26b. Moreover, ADSC-Exos promoted the regeneration of the myelin sheath by inhibiting SC autophagy in rat SNI models. In conclusion, our results indicated that ADSC-Exos promote the regeneration of the myelin sheath by moderately reducing autophagy of injured SCs via miRNA-26b downregulation of Kpna2. [ABSTRACT FROM AUTHOR]